Question

An electron is accelerated from rest through a potential difference of $V\text{volt}$. If the de Broglie wavelength of electron is $1.227$$\times {10}^{-2}$ $\text{nm}$, the potential difference is

• A. ${10}^3\text{V}$
• B. ${10}^4\text{V}$
• C. ${10}^2\text{V}$
• D. $10\text{V}$

Answer 1

The correct option is B ${10}^4\text{V}$

The de Broglie wavelength of an electron is given as:
$\lambda =\frac{1.227}{\sqrt{V}}$ $\text{nm}$
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Substitute the wavelength in the above expression:
$V={\left(\frac{1.227}{1.227\times {10}^{-2}}\right)}^2$

$V={10}^4\text{V}$